Climate-induced disasters

Story hook

It is 3 October 2023, just after midnight. South Lhonak Lake, perched at 5,200 metres in North Sikkim, has been swelling for decades — a textbook moraine-dammed proglacial lake fed by the retreating Lhonak Glacier. A cloudburst on the slopes triggers slope failure into the lake; the moraine dam fails; 50+ million cubic metres of water surge down the Teesta valley. Within four hours the wall hits Chungthang, smashing the 1,200 MW Teesta-III dam to rubble. Final toll: 77 dead, 142 missing, ~88,000 affected across four districts.

Eleven months later, on 30 July 2024, Wayanad in Kerala wakes to the sound of 426 people being buried alive. Two debris flows — each carrying boulders the size of trucks — sweep through Mundakkai, Chooralmala, Attamala and Noolpuzha villages. The trigger? 572 mm of rain in 48 hours on slopes the Gadgil Committee 2011 had flagged as ecologically sensitive.

Then on 31 July 2025, Dharali in Uttarkashi, Uttarakhand, is flattened by a flash flood. Cyclone Biparjoy (June 2023) had already broken the rule that Arabian Sea cyclones stay weak. 2024 was India's warmest year since 1901 at +0.65°C above the 1981-2010 average.

The pattern is no longer deniable: climate change has moved from forecast to forensic evidence. India — the world's third largest emitter but fourth most vulnerable to climate disasters — must now plan for compound, cascading, simultaneous events. This unit covers the IPCC science, India's Nationally Determined Contributions (NDC), LiFE Mission, and the climate-disaster nexus reshaping our DRR framework.

Why this matters for UPSC

GS-III explicitly lists "disaster and disaster management" and "environment" — and the climate-disaster nexus sits at the intersection. UPSC has asked climate-disaster questions in 2018, 2020, 2022, 2023, 2024 Mains — practically annual. Examiners want the linkage between IPCC AR6 findings, India's NDC update (August 2022), and India's adaptation architecture. Prelims hits IPCC working groups, NDC targets, NAPCC missions, LiFE, Panchamrit.